John Updike once said: 'I became a writer very young - one of those things where you get what you hope for and live with the consequences.' Delmore Schwartz, like Updike, became a writer very young and then spent most of his troubled life grappling with the consequences. The son of Jewish immigrants, Schwartz was born in Brooklyn in 1913. His father was an exuberant huckster, who made and lost a fortune, and his mother was a deeply erratic paranoid. Their marriage was a catastrophe.

Schwartz was a precocious teenager, an ardent and passionate reader who, by the time he was 20, had read all of the modernists and most of the philosophers, too. He was only 23 in 1937 when his marvellous first story, 'In Dreams Begin Responsibilities', was published in the Partisan Review, which was then one of the most influential political and cultural magazines in America.

'Those of us who read [the story] at the time really did experience a shock of recognition,' recalled Irving Howe, who was one of the leaders of the old Partisan Review crowd.

This shock of recognition has much to do with the way Schwartz wrote about the Jewish immigrant experience in New York. The precursor of Saul Bellow, Philip Roth and Bernard Malamud, Schwartz wrote of the strivings of clever, cultured young men who were intoxicated by the boundless potential of America but who, at the same time, were often ashamed of their ancestral inheritance and of how 'their parents spoke broken English or a foreign tongue', as Shenandoah Fish (Schwartz's fictional alter-ego) observes here in the story 'America! America!'.

'In Dreams Begin' tells of a boy visiting a cinema where he sees replayed on the big screen images from his parents' courtship. He watches as his anxious father arrives too early for a date at the house of the girl who will become his wife. He follows the young couple as they travel out to Coney Island and watches as the young man proposes marriage in a scene of gentle comedy.

At which point, the narrator rises from his seat and, in distress, shouts out: 'Don't do it. It's not too late to change your minds, both of you. Nothing good will come of it, only remorse, hatred, scandal, and two children whose characters are monstrous.'

Schwartz progressed to become one of the young stars of the Partisan Review and, more generally, of literary New York. He published more stories, poems, essays and reviews. He became good friends with, among others, Bellow, John Berryman and Mary McCarthy. Everyone wanted to know him.

But he never fulfilled his early promise, never wrote the great work of which he believed himself capable - his attempt at that great work, a long, autobiographical poem called Genesis was a grotesque self-indulgence. In truth, Schwartz was consumed and then destroyed by frustrated ambition. On the morning of his thirtieth birthday, he wrote in his journal: 'Too late, already too late.'

One of Saul Bellow's greatest novels, Humboldt's Gift (1975), is, in part, a subtle meditation on the defeated aspirations of Schwartz. Bellow once described seeing the aged Schwartz emerge dishevelled and probably drunk from his New York apartment. Rather than speak to his former friend, Bellow hid behind a car to avoid him. In the novel, this encounter is reimagined with considerable pathos as the Schwartz figure is portrayed stumbling towards death. 'He was gray stout sick dusty, he had bought a pretzel stick and was eating it. His lunch. Concealed by a parked car, I watched. I didn't approach him, I felt it was impossible.'

Bellow was not alone in finding it impossible to approach Schwartz towards the end of his life. Neurotic, alcoholic, drug-dependent, twice divorced, impecunious, he had become an embarrassment to all who knew him. Yet those who met Schwartz never forgot him or the brilliant boy he had been. They never forgot the turbulent intensity of his conversation or his belief in books and the dignity of the writing life.

Lou Reed, who dedicated his song 'European Son' to Schwartz, recently recalled how, as a young student in upstate New York, he had met the writer whom he describes as 'my teacher, friend, and the person who changed my life, the smartest, funniest, saddest person I'd ever met'. It was a bad time in Schwartz's life; the best was far behind him. Yet there was an immediate intimacy between them. Schwartz, Reed said, showed him how 'to take a poet or novelist's approach to songs, so the lyrics could stand alone but with the fun of the two guitars, bass and drums to enhance them'.

Delmore Schwartz spent the last years of his life beginning stories that he would never complete. His broken life always got in the way of his work, but it was his work - his fiction, his poems, his essays - that mattered most to him. He eventually died alone and largely forgotten in a midtown Manhattan hotel in 1966. His body was taken to the local morgue, where it remained unidentified for the next three days.

Many of the stories in this fine collection have a strange clairvoyance; they are dark with the threat of imminent catastrophe: such as the guest at a New York literary party who, in the story 'New Year's Eve', observes of the young writer Shenandoah: 'One day, he will fall flat on his face.'

Schwartz once remarked how the ideas of success and failure 'are the two most important things in America'. It was true that he wanted success above all else. But, in the end, what was most striking about him - his extreme precocity - was also his undoing. Schwartz may have been 'the poet of the historical moment', as Irving Howe said, but he did not really improve as a writer. His later fiction is flat and repetitive; his poems are simply dull.

Like Scott Fitzgerald, he did his best work before he reached 30. It could be said even that he did his best work before the age of 24, because he never wrote a finer story than 'Dreams'. From there, it was the long road to nowhere.